How does gravity affect the motions of Earth and the Moon?

The Sun's gravitational pull keeps our planet orbiting the Sun. The motion of the Moon is affected by the gravity of the Sun and Earth. Moon's gravity pulls on the Earth and makes the tides rise and fall.

Planetary Gravity

The Sun's gravitational pull keeps our planet orbiting the Sun. The motion of the Moon is affected by the gravity of the Sun AND the Earth. The Moon's gravity pulls on the Earth and makes the tides rise and fall every day. ... The Earth always produces the same acceleration on every object.

it has to be b, about 97 percent.